1. Field of the Invention
The present invention relates to an airbag device for a driver's seat and a front passenger seat equipped with a folded body of an airbag, an airbag cover for covering the folded body, an inflator for supplying an inflation gas to the airbag, and a bag holder for holding the respective parts, and a method of manufacturing the same.
2. Description of the Related Art
Conventionally, as an airbag device of this type, there has been an airbag device equipped with an airbag having an inflow opening for introducing the inflation gas, a bag holder that attaches a peripheral edge of the inflow opening to hold the airbag, an airbag cover that covers the periphery of the folded body of the folded airbag and is attached to the bag holder, and an inflator for supplying an inflation gas to the airbag (e.g., see JP-A-11-59309 A). In the airbag device, the airbag cover is configured to be formed of synthetic resin such as olefin-based thermoplastic elastomer (TPO), to cover the upper surface remote from the inflow opening of the folded body, and to have a ceiling wall having a door that is pushed open to the airbag when inflated. Furthermore, in the airbag device, a floating type hone switch mechanism is provided on the lower side, and a plurality of ribs with different lengths is provided to protrude from the ceiling wall of the airbag cover, in correspondence with a curved shape of the upper surface of the folded body. Therefore, if the ceiling wall of the airbag cover is pressed down by the ribs, even when the ceiling wall having elasticity is partially deflected via the folded body abutting on the ribs, the airbag device is lowered, thereby making it possible to turn ON the horn switch mechanism.
As another airbag device, after folding the airbag so that the folded body of the airbag can maintain a compact folded shape, by compression molding while heating, the deployment and inflation are allowed at the time of inflow of the inflation gas, but there is a case of forming the airbag to have a shape retaining property that prevents an easier folding collapse (e.g., see JP-T-2015-520065).
However, in the conventional airbag device, even if the folded body that is compression-molded is compactly configured so as to have a shape retaining property, if a large clearance occurs between the folded body and the airbag cover for covering the folded body, until the airbag cover made of synthetic resin such as olefin-based thermoplastic elastomer (TPO) comes into contact with the folded body, the folded body is greatly depressed, thereby lowering the tactility of the airbag cover. In particular, in a case where the folded shape itself of the airbag becomes compact depending on selection of a base fabric of a constitution material or the presence or absence of reinforcing cloth, when a configuration in which the compact folded body is attached to the bag holder is provided, a further larger clearance is generated between the folded body and the airbag cover, thereby promoting the above-mentioned problems. In this case, although it is conceivable to provide the aforementioned ribs on the lower surface of the ceiling wall of the airbag cover to cope with the problem, there is a problem of taking much time by an increase in changing locations, rather than simply adjusting the airbag itself to be changed.